Kinosternidae

Sternotherus odoratus

Wasserschildkroete-PICT0032

Kinosternon subrubrum

Lake Chapala Mud Turtle

Sternotherus carinatus by LA Dawson

Striped mud turtle (Kinosternon baurii)

Kinosternidae is a family of predominantly small, freshwater turtles known as mud turtles and musk turtles. This family is native to the Americas, ranging from southern Canada through South America. The family Kinosternidae is divided into four genera: Kinosternon, Sternotherus, Claudius, and Staurotypus. These turtles are characterized by their domed shells and their ability to excrete a foul-smelling odor from glands located near the tail, a defense mechanism against predators.

Description

Members of the Kinosternidae family vary in size but are generally small, with most species measuring less than 12 cm in shell length. They have sturdy, highly domed shells that can be smooth or keeled. The coloration of these turtles ranges from olive to dark brown, often with yellow or orange markings. Their plastron (the underside of the shell) is typically reduced in size, which allows for more flexibility and mobility in muddy or aquatic environments.

Habitat and Distribution

Kinosternidae turtles inhabit a wide range of freshwater habitats, including slow-moving rivers, swamps, ponds, and marshes. They are adept at burrowing and often spend a significant amount of time buried in mud or under vegetation, which provides camouflage and protection from predators. Their distribution spans from the southeastern parts of Canada, throughout the United States, and extends into Central and South America.

Behavior

Turtles of the Kinosternidae family are predominantly aquatic but can also be found in semi-aquatic environments. They are known for their secretive nature, spending much of their time hidden under mud or vegetation. These turtles are omnivorous, feeding on a variety of food sources such as insects, fish, crustaceans, and plant material. The ability to excrete a musky odor from their musk glands when threatened is a distinctive behavior that helps deter predators.

Reproduction

Kinosternidae turtles have varied reproductive strategies, with some species laying only a few eggs per clutch, while others may lay dozens. The eggs are typically buried in soft soils or leaf litter near water bodies. Incubation periods and the time to hatching can vary significantly among species. In many cases, the sex of the hatchlings is determined by the temperature at which the eggs are incubated, a phenomenon known as temperature-dependent sex determination.

Conservation

Several species within the Kinosternidae family are considered to be at risk due to habitat destruction, pollution, and the pet trade. Conservation efforts are in place in various regions to protect these turtles and their habitats. Research and monitoring are crucial for understanding the population dynamics and threats facing Kinosternidae turtles, to inform conservation strategies and actions.

Genera and Species

The Kinosternidae family includes the following genera and notable species:

• Kinosternon – Mud turtles
• Sternotherus – Musk turtles
• Claudius – Narrow-bridged musk turtle
• Staurotypus – Giant musk turtles

Each genus encompasses a variety of species adapted to specific environments and ecological niches within the Americas.